Nippon Shokubai Co., Ltd.

Nippon Shokubai Kagaku Kogyo Co., Ltd.

Nippon Shokubai Kagaku Kogyo Kabushiki Kaisha

Nobuaki Urashima

Mitsuo Kushino

Yoshikuni Mori

Hayato Ikeda

Yoshinori Sano

Kenji Minami

Masuji Izubayashi

Yoshihiro Arita

Kiyoshi Kawamura

Shigeru Tanimori

Tatsuhito Matsuda

Hironobu Toribuchi

Keiichi Uehara

Makoto Matsumoto

Nobuyuki Ando

Kazuhiro Anan

Iwao Fujikawa

Hayato Ideda

Iwao Fukikawa

An inorganic dispersion stabilizer having a hydrophobic inorganic oxide such as hydrophobic silica dispersed in an aqueous medium in the presence of an hydrophilic organic compound such as alcohol. An suspension polymerization process for producing resinous particles of a narrow particle diameter distribution by dispersing a monomer into an dispersion medium in the presence of the inorganic dispersion stabilizer, and polymerizing the monomer.

Inorganic dispersion stabilizer and process for producing resinous particles using the same

Carbon black graft polymer which comprises carbon black and a polymer chain grafted thereto, the carbon black having a specific surface area of not more than 120 m /g.

Carbon black graft polymer

A method which produces colored minute particles by suspending in an aqueous suspending medium a polymerizable monomer composition obtained by dispersing a coloring agent at least in a polymerizable monomer and polymerizing the resultant suspension is characterized in that the dispersion of the coloring agent in the polymerizable monomer is performed in the presence of a dispersing agent, the polymerizable monomer composition exhibits a viscosity of not more than 300 cP, and the suspension of the polymerizable monomer composition in the aqueous suspending medium exhibits a viscosity of not more than 100 cP. The dispersing agent is at least one resin selected from the group consisting of rosin derivatives, aromatic petroleum resins, pinene type resins, epoxy type resins, cumdrone resins, and styrene-acryl type resins.

Colored minute particles

Toner binder resin and static charge developing toner using the resin

A polymeric monomer (A) having as a main component thereof a (meth)acryl type monomer which is subjected to aqueous suspension polymerization in the presence of a compound (B) which is substantially insoluble in water and sparingly soluble in the polymeric monomer (A). The compound (B) has at least one, preferably two or more, structural units, selected from the group consisting of --SH, --S--S--, --COOH, --NO.sub.2, and --OH. The use of compound (B), in the suspension polymerization of the (meth)acryl type monomer, represses of the production of by-produced minute particles due to sympathetic emulsion polymerization. The suspension polymerization permits production of (meth)acryl type polymer particles having high heat stability and a small range of particle diameters.

Resinous particles, method for production thereof, and uses therefor

A suspension polymerization of a polymerizable monomer in the presence of an emulsion polymerization inhibitor is disclosed. The inhibitor is an aromatic series compound having a NO.sub.2 group, a SO.sub.3 Na group, and a secondary amino group, representatively, the following compound. In this suspension polymerization, the production of by-produced microfine particles caused by the emulsion polymerization as the secondary polymerization scheme is repressed. ##STR1##

Emulsion polymerization inhibitor and suspension polymerization method

A polymeric monomer (A) having as a main component thereof a (meth)acryl type monomer which is subjected to aqueous suspension polymerization in the presence of a compound (B) which is substantially insoluble in water and sparingly soluble in the polymeric monomer (A). The compound (B) has at least one, preferably two or more, structural units, selected from the group consisting of --SH, --S--S--, --COOH, --NO.sub.2, and --OH. The use of compound (B), in the suspension polymerization of the (meth)acryl type monomer, represses of the production of by-produced minute particles due to sympathetic emulsion polymerization. The suspension polymerization permits production of meth)acryl type polymer particles having high heat stability and a small range of particle diameters.

Coloring fine particles produced by heating spheroidal coloring fine particles with an average fine particle diameter of 1-100 .mu.m obtained by suspension polymerization to a temperature of 30.degree. to 200.degree. C., thereby causing the particles to fuse together in a block without completely destroying the particle interfaces, and then crushing the block to substantially the same average particle diameter of the spheroidal coloring particles before melting, and a toner for developing electrostatic images using the same.

Coloring fine particles and toner for developing electrostatic images

Coloring fine particles produced by heating spheroidal coloring fine particles with an average fine particle diameter of 1-100 .mu.m obtained by suspension polymerization to a temperature of 30.degree. to 200.degree. C., thereby causing the particles to fuse together in a block without completely destroying the particle interfaces, and then crushing the block to substantially the same average particle diameter of the spheroidal coloring particle before melting, and a toner for developing electrostatic images using the same.

Coloring fine particle and toner for developing electrostatic images

A carbon black-graft polymer, produced by causing a polymer possessing within the molecular unit thereof at least one reactive group selected from the class consisting of aziridine group, oxazoline group. N-hydroxyalkylamide group, epoxy group, and thioepoxy group to react with carbon black. The polymer can be used as a toner for electrostatically charged image, resin composition, coating composition, ink for thermographic transfer, coating agent for magnetic recording medium, rubber composition, and carbon black dispersion and the like.

Carbon black-graft polymer, method for production thereof, and use

Colored microfine globular particles are produced by causing carbon black to react with a polymer capable of reacting with the carbon black thereby forming a carbon black-graft polymer, dispersing this carbon black-graft polymer in a polymerizable monomer component, and then polymerizing the polymerizable monomer component. These particles, in the unmodified form, are usable as a toner for the development of images of static charge and, in a form incorporated in a varying component, are usable such as in resin composition, coating composition, thermosensitive transfer ink ribbon coating agent, thermosensitive transfer ink, or back-coating agent for magnetic recording medium.

Colored microfine globular particles, method for production thereof, and

A carbon black-graft polymer, produced by causing a polymer possessing within the molecular unit thereof at least one reactive group selected from the class consisting of aziridine group, oxazoline group. N-hydroxyalkylamide group, epoxy group, and thioepoxy group to react with carbon balck. The polymer can be used as a toner for electrostatically charged image, resin composition, coating composition, ink for thermographic transer, coating gent for magnetic recording medium, rubber composition, and carbon black dispersion and the like.

Colored microfine globular particles, method for production thereof and

A carbon black-graft polymer, produced by causing a polymer possessing within the molecular unit thereof at least one reactive group selected from the class consisting of aziridine group, oxazoline group. N-hydroxyalkylamide group, epoxy group, and thioepoxy group to react with carbon black. The polymer can be used as a toner for electrostatically charged image, resin composition, coating composition, ink for thermographic transer, coating gent for magnetic recording medium, rubber composition, and carbon black dispersion and the like.

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Takatsuki, Japan

Nobuaki Urashima